Endocrine Abstracts

Background: The clinical attitude to the treatment of Bethesda System Category III lesions has been under controversy. Our aim was to analyse three variables and to establish a possible predictive value for carcinoma in patients with AUS/FLUS nodules.

Methods: Retrospective study of 671 thyroid fine-needle aspirations (FNAs) classified as AUS/FLUS between January 2012 and June 2015. Size, sex and age were analysed, using SPSS.

Results: 671 (14.8%) FNAs were initially classified as Bethesda’s category III, in a database of 4549 FNAs from 3696 patients. 195 patients underwent surgery. The risk of malignancy for operated patients was 29.7%. Nodule mean size was 24.4mm. Nodules were bigger in men than in women (27mm/24mm). The median size for histologically benign nodules was 26.5mm while malignant nodules had a median of 25mm. Follicular carcinomas were larger than papillary carcinomas (34mm/26.8mm). The histologic follow-up revealed a prevalence of malignancy for women (30.7% vs 24.1%) and for younger ages. The median for histologically benign nodules was in the 6^th decade while for carcinomas was in the 5th.

Conclusion: Age was the only variable with predictable value for carcinoma in AUS/FLUS. The probability of carcinoma reduces 3% per year according to a multifactorial analysis. Patients over 70s have 5 times less probability of carcinoma than those under 40s. According to that, the authors suggest that surveillance may be enough for patients over 70s with AUS/FLUS nodules.